The present invention relates to members used in construction, especially in applications where sound attenuation and sound isolation is important. In particular, the present invention relates to construction members used to construct building structures in which sound transmission from one room to another is to be prevented or reduced.The present invention also relates to a system for retrofitting a pre-existing standard wall frame with an improved stud construction which improves sound attenuation characteristics across the wall.
Standard wall frame systems including a plurality of interconnected individual stud have long been used to construct walls. Also, in general, it is conventionally known to resiliently mount a wall or ceiling in order to isolate sound or attenuate transmission therethrough.
U.S. Pat. No. 3,445,975 to Nelsson discloses a partition in which first and second lath panels are held against a metallic stud, channel, or furring member by a clip fastener. One portion of the stud, channel, or furring member is cantilevered away from the portion at which the lath panels are clipped thereto. According to Nelsson, this permits the free portion of the stud, channel, or furring member to flex as the lath panels mechanically respond to sound waves incident thereon. The remainder of the structure dampens this surface movement, reducing sound transmission to the opposite surface of the partition.
U.S. Pat. No. 3,324,615 to Zinn discloses a construction member having a plurality of laterally extending supporting tabs by which wallboard segments are resiliently mounted.
U.S. Pat. No. 3,046,620 to Tvorik et al. discloses a ceiling hanger member whereby a furring strip (to which a ceiling member is attached) is resiliently attached to a joist, such that the weight of the furring strip and ceiling member resiliently separates the furring strip from the joist.
Another known method of sound attenuation is to build a wall frame in which individual studs are laterally staggered relative to a toe plate and head plate. Therefore, alternate studs are used to mount wall board on respective sides of the frame so that a given stud is spaced away from one of wall boards.
Unfortunately, the foregoing conventional methods of noise attenuation are problematic in that they generally move away from basic construction methods and thereby increase complexity and cost. For example, they require additional parts (such as Tvorik et al. and Nelsson) or specially made parts (such as the channel member with specially formed support tabs, as in Zinn). The staggered stud arrangement necessarily results in a thicker wall partition which reduces the area of the room whose walls are framed in this manner, and increases the cost of the toe and head plates.
In addition, nail fasteners generally cannot be used with metal members, thereby undesirably restricting available construction methods.
Finally, a standard wall frame system must generally be completely torn down to put a conventional sound attenuating systems into place. It would be therefore desirable to be able to retrofit a standard wall frame system so as to increase its sound attenuation characteristics.
In addition to the devices for sound attenuation described hereinabove, a wood I-beam is commercially available (e.g., under the brand name xe2x80x9cBCI Advantagexe2x80x9d from Boise Cascade Corporation) that comprises a pair of wood members with a rigid wooden panel extending therebetween. However, because the wooden panel is essentially non-resilient, this I-beam offers little or no sound attenuation benefit.
The present invention is therefore most generally directed to a construction member that relies on resilient flexibility in order to attenuate sound transmission therethrough, but also more closely conforms to conventional building members in order to minimize or eliminate the need for any special handling or the like in use.
In particular, the present invention is directed to a construction beam member which are comparable in size to conventional wood beams (e.g., 2xe2x80x3xc3x974xe2x80x3 or 2xe2x80x3xc3x976xe2x80x3). The beam comprises a pair of spaced of lateral members having at least one resilient web extending therebetween. The web is preferably relatively stiff, but permits a slight flexure between the lateral members. The lateral members are preferably made from an easily workable material such as wood.
In addition, the web is preferably provided with one or more spacers so as to facilitate the arrangement of the respective lateral members relative to each other and relative to the web. In part, this facilitates the assembly of the lateral members relative to each other and to the lateral web so as to obtain a beam member according to the present invention.
In a particular embodiment of the present invention, a retrofit system comprising one lateral member having a resilient web attached thereto is provided. The resilient web is provided with one or more spacers so that the one lateral member having the resilient web attached thereto can be easily positioned relative to a respective beam in a standard wall frame construction, thereby imparting the sound attenuation benefits of a frame using resilient construction beams without needing to completely tear down the original structure. In this arrangement, respective beams in the standard wall frame act as the other lateral member of the beam according to the present invention.